Conventional note counting machines are not provided with a cover or a shutter for covering the counting zone. The reason for not providing a cover has been that the provision of a cover would obviously result in inconvenience when bundles of notes are inserted into and removed from the counting zone, one after another. The cover would also decrease the efficiency of their operation.
However, because of the lack of a cover, the conventional note counting machine has been burdened with two main disadvantages. Firstly, the counting machine produces a relatively loud noise in the counting zone, and this noise is annoying to the operator and other persons nearby. Secondly, dust on the notes escapes into the surrounding air during the counting operation, thus degrading the environment in the vicinity of the machine. In order to prevent the dust from escaping from the counting zone, the conventional note counting machine is provided with a dust collecting device which collects the dust generated in the counting zone. However, the dust collecting device can collect only a part of the dust. Therefore, it is not satisfactory.